In certain states, such as Maryland, Massachusetts, New Jersey, and Pennsylvania, homeowners receive Solar Renewable Energy Certificates or Credits (SRECs) for generating solar electricity. They can sell or participate in SREC trade in their local SREC market.
SREC prices can fluctuate and are determined by:
The SACP is the price electricity suppliers, such as utility companies, must pay if they don’t meet their renewable energy targets. Renewable energy targets are set by the state’s Renewables Portfolio Standard (RPS). RPS programs require electricity suppliers to get a certain portion of their energy from renewable sources.
Because homeowners can sell their SRECs for additional income, SRECs help lower the net cost of going solar. As you produce more and more solar electricity over time, you’ll earn more and more SRECs to sell. Start saving with solar by getting a free solar quote.

In their own words: Sunrun customers speak about getting home solar.